Identifying the lithospheric structure of a Precambrian orogen using magnetotellurics: The Capricorn Orogen, Western Australia

Selway, Kate; Sheppard, S. C.; Thorne, A. M.; Johnson, Simon P.; Groenewald, P. B.

doi:10.1016/j.precamres.2008.09.010

Cited by 23 publications

(16 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These velocity data indicate that changes in crustal structure extend through the seismogenic thickness of the crust and therefore may be preferential zones for accommodating crustal strain. A similar boundary also was detected in magneto-telluric data (Selway et al 2009) and is proposed to coincide with the Talga Fault (the proposed suture between the Pilbara Craton and Glenburgh Terrane). Sutures identified in both the tomographic and magneto-telluric data underscore the long-lived nature of the fundamental crustal boundaries that exist in the region, and which may now form the locus for present-day deformation.…”

Section: Discussionsupporting

confidence: 74%

Natural seismicity and tectonic geomorphology reveal regional transpressive strain in northwestern Australia

Keep

Hengesh

Whitney

2012

Australian Journal of Earth Sciences

View full text Add to dashboard Cite

Section: Discussionsupporting

confidence: 74%

Natural seismicity and tectonic geomorphology reveal regional transpressive strain in northwestern Australia

Keep

Hengesh

Whitney

2012

Australian Journal of Earth Sciences

View full text Add to dashboard Cite

“…For example, the Central Australian Suture Zone, which forms the contact between the North Australian craton and the Proterozoic Warumpi province [ Selway et al , , ], is mapped as a dipping conductor. Also, in Australia, the Errabiddy Shear Zone forms a conductive suture between the Yilgarn Craton and the Glenburgh Terrane [ Selway et al , ]. The margin between the Slave craton and the Wopmay orogen [ Spratt et al ., ] is preserved as steeply dipping conductive structure.…”

Section: Discussionmentioning

confidence: 99%

Lithospheric structure of an Archean craton and adjacent mobile belt revealed from 2‐D and 3‐D inversion of magnetotelluric data: Example from southern Congo craton in northern Namibia

et al. 2013

View full text Add to dashboard Cite

[1] Archean cratons, and the stitching Proterozoic orogenic belts on their flanks, form an integral part of the Southern Africa tectonic landscape. Of these, virtually nothing is known of the position and thickness of the southern boundary of the composite Congo craton and the Neoproterozoic Pan-African orogenic belt due to thick sedimentary cover. We present the first lithospheric-scale geophysical study of that cryptic boundary and define its geometry at depth. Our results are derived from two-dimensional (2-D) and three-dimensional (3-D) inversion of magnetotelluric data acquired along four semiparallel profiles crossing the Kalahari craton across the Damara-Ghanzi-Chobe belts (DGC) and extending into the Congo craton. Two-dimensional and three-dimensional electrical resistivity models show significant lateral variation in the crust and upper mantle across strike from the younger DGC orogen to the older adjacent cratons. We find Damara belt lithosphere to be more conductive and significantly thinner than that of the adjacent Congo craton. The Congo craton is characterized by very thick (to depths of 250 km) and resistive (i.e., cold) lithosphere. Resistive upper crustal features are interpreted as caused by igneous intrusions emplaced during Pan-African magmatism. Graphite-bearing calcite marbles and sulfides are widespread in the Damara belt and account for the high crustal conductivity in the Central Zone. The resistivity models provide new constraints on the southern extent of the greater Congo craton and suggest that the current boundary drawn on geological maps needs revision and that the craton should be extended further south.

show abstract

“…This is a surprising result as separate crustal blocks often show differences in their electrical character (e.g. Jones et al 2005;Selway et al 2009b). The high resistivity of the Musgrave Province is likely to be due to its high-grade, anhydrous nature imparted during the Musgravian Orogeny .…”

Section: Discussionmentioning

confidence: 99%

Magnetotelluric constraints on the tectonic setting of Grenville-aged orogenesis in central Australia

Selway

Hand

Payne

et al. 2011

JGS

View full text Add to dashboard Cite

Magnetotelluric (MT) data were collected over a 480 km long profile in central Australia, extending from the Mesoarchaean-Palaeoproterozoic Gawler Craton into the Mesoproterozoic-Neoproterozoic Musgrave Province. The two regions have contrasting geological histories and many reconstruction models of Proterozoic Australia propose that they were juxtaposed during the Mesoproterozoic. Despite the significant differences in geological background between the Gawler Craton and the Musgrave Province, the MT data did not image an electrical structure, or any change in electrical character, between them. MT models suggest that southern-central Australia is electrically separated into two parts. The first, comprising the northernmost Gawler Craton and the Musgrave Province, has a 5 km thick layer of moderate resistivity overlying highly resistive crust. The second, comprising the central-northern Gawler Craton, displays moderate resistivity to the base of the crust. The lithospheric mantle underlying both electrical regions is uniformly highly resistive. Our results suggest that the Musgrave Province and Gawler Craton are more closely related than is currently recognized. We propose that the Gawler Craton forms basement to the Musgrave Province and that the Grenvillian Musgrave Orogeny was an intracratonic reworking event that overprinted the older basement.

show abstract

Identifying the lithospheric structure of a Precambrian orogen using magnetotellurics: The Capricorn Orogen, Western Australia

Cited by 23 publications

References 39 publications

Natural seismicity and tectonic geomorphology reveal regional transpressive strain in northwestern Australia

Natural seismicity and tectonic geomorphology reveal regional transpressive strain in northwestern Australia

Lithospheric structure of an Archean craton and adjacent mobile belt revealed from 2‐D and 3‐D inversion of magnetotelluric data: Example from southern Congo craton in northern Namibia

Magnetotelluric constraints on the tectonic setting of Grenville-aged orogenesis in central Australia

Contact Info

Product

Resources

About